Questions tagged [programming]
The process of designing and writing source code as part of a program (or sketch) for Arduino. For questions about uploading code to an Arduino board, use the [uploading] tag instead.
123 questions
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How can I handle the millis() rollover?
I need to read a sensor every five minutes, but since my sketch also has
other tasks to do, I cannot just delay() between the readings. There
is the Blink without
delay tutorial
suggesting I code ...
- 45.2k
21
votes
3
answers
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Classes and objects: how many and which file types do I actually need to use them?
I have no previous experience with C++ or C, but know how to program C# and am learning Arduino. I just want to organize my sketches and am quite comfortable with the Arduino language even with its ...
- 503
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answer
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How do you combine 2 different sketches together
(Before you down-vote this, note that it is a "ringer" to answer a FAQ, with a self-answer.)
This question comes up all the time. How do you combine 2 different sketches together? Say I have a sample ...
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votes
22
answers
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What are the other IDEs for Arduino?
The basic Arduino IDE lacks a lot of the sophistication present in other IDEs such as code completion, code collapsing, folder organisation, etc. Are there other IDEs that allow programming in C or C++...
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answers
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Is using malloc() and free() a really bad idea on Arduino?
The use of malloc() and free() seems pretty rare in the Arduino world. It is used in pure AVR C much more often, but still with caution.
Is it a really bad idea to use malloc() and free() with ...
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41
votes
10
answers
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Arduino Nano uploading gives error: avrdude: stk500_recv(): programmer is not responding
I have a Arduino Nano (Sainsmart) that I'm trying to upload a sketch to. Under the Arduino IDE, the device selected was Arduino Nano w/ ATmega328.
However uploading the sketch gives me the error
...
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Can the 2nd MCU on the UNO R3 be used for keyboard emulation?
Following on from What's the 2nd ICSP header for in Arduino Uno R3? I was wondering how this could be hacked to our advantage.
For example, could that firmware be rewritten to have the UNO ...
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41
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10
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Programming an Arduino using Python, rather than C/C++
I am not very skilled with the C Language and I was wondering if there is a way in which python could be used to program an Arduino. This would most likely require a different IDE in order to be able ...
- 1,903
4
votes
4
answers
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class enum was not declared in this scope
I am programming an Arduino. In the same .ino file as setup() and loop() I have defined the following:
void setup()
{
// setup code
}
enum class CYCLE { TypeA, TypeB };
String cycleToString (...
- 181
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votes
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answers
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Getting a truly random number in Arduino
What is the best method to get a truly (as opposed to pseudo) random number in Arduino, or at least the best possible approximation? From my understanding, the function randomSeed(analogRead(x)) it's ...
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Use object of other class within class
I am writing a class for a project which will take care of handling any LCD updates for my project. The way I want to handle this is to initialize the LCD object in my main file, and then pass the LCD ...
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Is it better to use #define or const int for constants?
Arduino is an odd hybrid, where some C++ functionality is used in the embedded world—traditionally a C environment. Indeed, a lot of Arduino code is very C like though.
C has traditionally used #...
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votes
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How to add hysteresis to threshold values?
This code compares the analog input value against two thresholds, having three voltage regions. Then it will turn on an LED according to what region the read voltage is in.
The problem is that when ...
- 103
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How to combine two different sensor sketches to one complete sketch?
How to combine two different sensor sketches to one complete sketch for a complete circuit that attaches to one Arduino Uno?
Sharp Dust Sensor
int measurePin = A0; // Connect dust sensor to Arduino ...
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answers
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What happens when I call exit() from my program?
In either of setup or loop, if I were to add an exit(0) call, where would control be passed to? What would the next state of the microcontroller be? Would it stop execution and power down?
I am using ...
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